This invention relates to a unique stowage system for a tail ramp toe of a cargo aircraft and, more particularly, to such a system adapted for use in, and with, a cargo aircraft of the "short takeoff and landing" type (hereinafter referred to as the "STOL" type).
Cargo aircraft, particularly those of the STOL type, need and have auxiliary tail ramp toes or the like which bridge the height from the aft end edge of the tail ramp to the ground during ground loading, or ground off-loading, of the cargo. More specifically, the YC-15 Advance Medium STOL cargo aircraft has two such auxiliary tail ramp toes; and, the toes are removably attached to the tail ramp with an actuatable torque tube, and other associated components, such as are disclosed in the above-identified U.S. Pat. No. Application (i.e., "Ramp With Integral Toes," Ser. No. 643,506, now U.S. Pat. No. 4,032,092). That torque tube permits the tail ramp toes to be lowered to the ground during loading of cargo. After loading and to prepare for flight, the tail ramp is raised, by and with the use of the torque tube, and the tail ramp toes are automatically rotated up and forward, until their upper surface is approximately at 90 degrees with the internal surface of the tail ramp.
It is here to be noted that cargo aircraft usually have (and the Y-15 STOL cargo aircraft does have) a downwardly and outwardly opening tail ramp, and a complementary upwardly and inwardly opening tail door aft of the tail ramp. Accordingly, the tail ramp is closed by being raised inwardly, and the tail door is closed by being lowered outwardly.
Therefore, with the tail ramp and the toes of the YC-15 cargo aircraft in the above-stated position, the tail door (also sometimes referred to in the art as the "cargo door") is closed by being lowered (i.e., rotated downwardly). Additionally, in the YC-15 cargo aircraft, for aerial delivery), the tail ramp toes are removed manually from the tail ramp, and are stowed on the upper structure of the tail door (i.e., the "cargo door"). The tail door is then raised upwardly and inwardly, and the cargo is delivered (i.e., dropped) off the aft end edge of the trail ramp.
We have invented a ramp toe stowage system that is simple in structure, is light in weight, is safe (i.e., positively restrains the stowed toe(s) at all times), and requires only one man to stow (or to remove from stowage) the toe(s) while the cargo aircraft is in flight, despite the fact that each toe weighs approximately 160 pounds. The system is well suited for all cargo aircraft of the type described, and is ideal for use in and with the YC-15 cargo aircraft.
The invention fulfills a current need in the art; and, therefore, it significantly advances the state-of-the-art.